1. Field of the Invention
The present invention generally pertains to medical and surgical apparatus, and more particularly, pertains to laser ablation catheters.
2. Description of the Prior Art
It is known in the art to use laser energy for medical purposes. A common medical application is in the irradiation of biological tissue. For external use, the laser energy may be directly applied. However, when the procedure requires irradiation of tissue which is not readily accessible, the use of a laser catheter is common. A typical application for a laser catheter is in the cardiovascular system. U.S. Pat. Nos. 4,997,431 and 4,985,028, both issued to Isner et al., show laser catheters particularly adapted for laser ablation within the cardiovascular system.
Multi-fiber systems have been particularly important in medical applications where laser energy must be transmitted from the laser power source to some location inside the human body. These configurations are needed to maintain a small diameter catheter for percutaneous introduction while providing a flexible catheter to negotiate the tortuous pathways in the cardiovascular system. However, when the medical applications require substantial laser power to be delivered over long periods of time, the traditional connector systems, such as described in U.S. Pat. No. 4,526,170, issued to Tanner, have proven inadequate.
U.S. Pat. No. 4,383,729, issued to Suzuki et al., shows a multi-fiber connector wherein a single beam of energy is split into component parts for transmission along a multiple fiber cable. However, such connectors may have difficulty handling the energy which is not intercepted by the optical fibers, and as a result the connector may be thermally damaged.